Fault codes -o2 and secondary air flow

[dleb]

I have a 1998 m3 with 87,000 miles. I have not had the car very long and the other day got the CEL. I checked the codes and got 2 faults for after cat o2 sensor heater and one for secondary air system flow too low (cyl 4-6). I have an AA trackpipe, no cats. I'm wondering if a lack of cats is the cause, should i look at this differently because i dont have cats, or the same as if I did?

I havent driven much but it seems to run fine. I had one rough cold start but the air pump was whirring along with no strange noises (although i am far from an expert).

Thoughts would be appreciated. Thanks.

[BPMSport]

Originally Posted by dleb

I have a 1998 m3 with 87,000 miles. I have not had the car very long and the other day got the CEL. I checked the codes and got 2 faults for after cat o2 sensor heater and one for secondary air system flow too low (cyl 4-6). I have an AA trackpipe, no cats. I'm wondering if a lack of cats is the cause, should i look at this differently because i dont have cats, or the same as if I did?

I havent driven much but it seems to run fine. I had one rough cold start but the air pump was whirring along with no strange noises (although i am far from an expert).

Thoughts would be appreciated. Thanks.

It shouldn't be related to not having cats as long as all the sensors are plugged in. You should check for the correct voltages and make sure they are getting powered. Check for fuses that are out. You might need new oxygen sensors.

As far as the secondary air system too low, that could be a number of different things.

Good luck.